This invention relates to improvement in a single lever control unit for operating the clutch and throttle mainly of a marine engine.
Several control units of this type have heretofore been provided, but each of them has its own advantage and disadvantage. Particularly, single lever control units require means for disengaging the clutch actuating member for the warming up of the engine. Since the disengaging means is operated from outside the casing by a shift rod which is provided independently of the lever shaft, seawater ingresses into the disengaging means every time the shift rod is pulled out or pushed in, resulting in the deposition of salt which causes a trouble to the interior mechanism and possibly renders the mechanism inoperative.
Another structure is known in which the shift rod is integral with the lever shaft, such that the clutch actuating member is disengaged or engaged by pulling out or pushing in the lever shaft. With this structure, the number of the portions permitting the ingress of seawater into the interior of the casing is reduced, so that the structure has correspondingly improved waterproofness. However, when the lever shaft is operated as above, the throttle operating member moves axially of the lever shaft, consequently bending a control cable which is pivoted at it one end to the throttle operating member. The end of the control cable in the bent state is pivotally moved by the turn of the throttle operating member. This movement increases the friction between the sheath of the control cable and its inner wire (which is usually connected to the throttle operating member by a nonflexible rod), reducing the durability of the control cable and also impairing smooth operation of the lever. Moreover, the structure has another drawback that when the lever shaft is in its pushed-in position within the casing, the disengaging means is entirely unprotected from water.